es6-lint

.eslintrc.json

{
  "env": {
    "es6": true,
    "node": true
  },
  "extends": "eslint:recommended",
  "parserOptions": {
    "ecmaVersion": 8
  },
  "rules": {
    "indent": ["warn", 4],
    "quotes": ["error", "single"],
    "semi": ["error", "always"],
    "no-else-return": ["error"],
    "no-invalid-this": ["error"],
    "no-return-await": ["error"],
    "require-await": ["error"],
    "array-bracket-spacing": ["warn", "never"],
    "array-bracket-newline": ["warn"],
    "brace-style": ["warn", "1tbs"],
    "block-spacing": ["warn", "always"],
    "comma-dangle": ["warn", "only-multiline"],
    "comma-spacing": ["warn"],
    "key-spacing": ["warn"],
    "keyword-spacing": ["warn"],
    "new-parens": ["error"],
    "no-lonely-if": ["error"],
    "no-multiple-empty-lines": ["warn"],
    "padding-line-between-statements": [
      "warn",
      { "blankLine": "always", "prev": "*", "next": "function" },
      { "blankLine": "always", "prev": "*", "next": "return" }
    ],
    "padded-blocks": ["warn", { "classes": "always" }],
    "no-multi-spaces": ["warn"],
    "no-trailing-spaces": ["warn"],
    "no-unneeded-ternary": ["warn"],
    "object-curly-newline": ["warn"],
    "object-curly-spacing": ["warn", "always"],
    "space-infix-ops": ["warn"],
    "space-unary-ops": [2],
    "no-useless-constructor": ["error"],
    "no-var": ["error"],
    "prefer-const": ["error"],
    "prefer-rest-params": ["error"]
  }
}